minerals

Question 1

Mineraloids

Answer 1

NO CRYSTAL STRUCTURE - AMORPHOUS

can be man-made (synthetic diamonds) or natural (coal, oil etc.)

Question 2

Minerals

Answer 2

CRYSTAL structure

Question 3

crystal shape reflects

Answer 3

arrangement of atoms

Question 4

75% of earths crust comprise

Answer 4

oxygen and silicon

Question 5

3 bonding types in minerals

Answer 5

ionic, covalent, metallic

Question 6

anion

Answer 6

negative

Question 7

cation

Answer 7

positive

Question 8

coordination number

Answer 8

number of anions around each cation in a crystal lattice

Question 9

unit cell

Answer 9

smallest arrangement of atoms which may be repeated regularly in 3d to form the crystal lattice

Question 10

mineral growth

Answer 10

• start as a seed
• grow out from centre
• outside new inside old

Question 11

IGNEOUS Minerals

Answer 11

• high temperature, melting
• free environement
• moderate to hard minerals
• good crystal shape

Question 12

METAMORPHIC Minerals

Answer 12

• moderate-high temp
• no melting
• low-high pressure
• moderate to hard minerals
• poor crystal shape

Question 13

GEOTHERMAL Minerals

Answer 13

• moderate temp
• low pressure
• soft, hydrous minerals
• good crystal shape

Question 14

WEATHERING Minerals

Answer 14

• low pressure and temp (Earth’s surface)

- minerals are soft, hydrous and have good crystal shape

Question 15

clays, low temp oxides and evaporates are…

Answer 15

formed through weathering

Question 16

sulphides, gold, silver are…

Answer 16

geothermal formed

Question 17

hardness

Answer 17

resistance to abrasion and strength of atomic bonds

Question 18

cleavage

Answer 18

tendency to split along plane ( weak bonds)

Question 19

how does mineral break when lacking weak planes

Answer 19

fracture

Question 20

specific gravity

Answer 20

density

Question 21

what controls colour

Answer 21

small variation in composition

Question 22

streak

Answer 22

colour of powdered mineral, more diagnostic than colour

Question 23

silicate minerals make up ____ of the earths crust

Answer 23

95%

Question 24

structure of silicate

Answer 24

tetrahedral

Question 25

5 silicate structural groups, in increasing complexity / increased cooling time / decreased cooling temp

Answer 25

1. isolated tetrahedral - dense 2. single chain structure - pyroxene minerals 3. double chain - amphibole minerals 4. sheet structure - clays, micas 5. framework - shares all 4 oxygens, eg quarts

Question 26

ferromagnesian minerals: contain, colour, weight

Answer 26

Fe, Mg dark colour dense

Question 27

non-ferromagnesian minerals: contain, colour, weight

Answer 27

light colour, less dense

Question 28

main features of carbonates

Answer 28

- low density - light colour - form through ppt. - major component of cement

Question 29

most abundant non-silicate group

Answer 29

Carbonate

Question 30

what is calcite?

Answer 30

most common carbonate. found in bones and shells

Question 31

SULPHIDES

Answer 31

- sulphide anion (s2-) bonded to metal - look metallic - ppt. from geothermal waters

Question 32

sulphates from through...

Answer 32

evaporation

Question 33

hailde features

Answer 33

- soft - transparent - low density - good cleavage - bright colours Eg table salt